Switching mechanism



1m 6, 1940 s. J. STOCKFLETH 2,187,571

SWITCHING MECHANISM Filed Feb. 21, 1939 2 Sheets-Sheet 1 lNl ENTOR By 5. J. S TOC/(FLE T H A T TORNE V 1940- s. .1. STOCKFLETH SWITCHING MECHANISM Filed Feb. 21, 1939 2 Sheets-Sheet 2 INVENTOR S. J. STOCKFLETH W W q A T TOR/V5 V Patented Jan. 16, 1940 UNITED STATES PATENT OFFICE SWITCHING MECHANISM Application February 21, 1939, Serial No. 257,684

Claims.

This invention relates to improvements in switching mechanisms and particularly in switches of the cross-bar type for use in establishing electrical connections.

It is an object of this invention to improve and simplify switches of this kind to cause them to perform their functions with greater accuracy and reliability.

Cross-bar stitches to which the present invention may be applied are well known in the art and consist essentially of contact sets arranged in horizontal and vertical rows and means including a group of horizontal operating members intersecting a. group of vertical operatingmembers controlled by magnets. In some type of switches the horizontaloperating members are rotatable in two directions so that connections may be established at either of two sets of contacts at an intersecting point by the rotation of a horizontal bar in one direction or the other and the rotation of a vertical bar in one direction.

The present invention has been disclosed in connection with a cross-bar switch of this latter type and particularly with a switch of the type disclosed in the patent to J. N. Reynolds 2,021,329 of November 19; 1935. In thisswitch the rotation of a horizontal bar causes a selecting finger to' be placed opposite an actuating spring to select a set of contacts. When a vertical bar is operated, it causes this finger to be pressed against the actuating spring which in turn causes a connection to be established between the contact sets at the corresponding cross-connecting point. The actuating springs operate on insulation studs placed between one set of springs to be actuated to close connections with the corresponding set of springs at the cross-points;

It is a feature of the present invention to provide improvements whereby these actuating springs and insulation studs are replaced by a specially constructed actuating card for each set of contacts on which the selecting finger may act directly when a vertical bar is operated.

While this feature of the invention may be realized by difierent embodiments, the one illustrated herein shows a card having slots cut di- The card is prevented angles to the slots in a circular hole at the bottom of the bifurcation, and the card is prevented from turning after being once located by indentations on the springs on one side and by lying fiat against the inner surface of the horizontal contacts in the vertical unit on which individual rows of vertical contact springs are mounted.

The invention has been illustrated in the accompanying drawings in which:

Fig. 1 shows a front view of a cross-bar switch structure of the type disclosed in the above-mentioned patent and to which the applicants invention has been applied.

Fig. 2 shows a side view of one of the vertical units in this cross-bar switch structure.

Fig. 3 shows a fragmentary view in perspective of the contact springs at a cross-point, a vertical bar with its operating magnet and a selecting finger and a portion of a vertical bar and its operating magnet.

Fig. 4 shows an enlarged view taken from the front of a vertical unit disclosing two of the cards in accordance with the applicants invention and the associated contact springs, with the selectin finger in cross-section and looking in the direction of the arrows 4-4 as indicated on Fig. 2.

Fig. 5 shows a cross-section of a card and a fraction of a contact spring in which the card is inserted.

Referring now to the drawings and particularly to Figs. 1 and 2, the switch structure to which applicants invention may be applied may consist as disclosed in these figures of a frame comprising the members i, 2, 3 and 4, five horizontal bars 5 and a series of ten vertical bars, the first, second and last of these latter bars have been shown only as comprising the first, second and last of the ten vertical units. These bars have been indicated with the numerals 6, 7 and 8, respectively. The horizontal and vertical rows of contact strips mounted in these three units have been shown. The first set of horizontal contacts in the first horizontal row have been marked l3 and the first vertical row of contact springs has been marked I4 while the first horizontal contacts of the second horizontal row have been marked IS. The card for establishing connections between the contacts l3 and M has been marked l6 and the card for establishing connections between these contacts l4 and I5 has been marked IT.

The first or upper horizontal bar 5 may be actuated to rotate the actuating finger such as I8 to select the upper row of horizontal contacts l3 by the operation of the magnet 20 and to select the second row of horizontal contacts I5. This upper horizontal bar 5 may be actuated by the magnet 2|. The vertical operating bars 6, 1 and 8 may be rotatably guided on the supporting members 22 and be actuated by magnets 23, 24 or 32 to establish connections that will be hereinafter described in detail. The members 22 are secured to the upper and lower horizontal bars I and 2 while the horizontal bars are pivotally supported between the frame members 3 and 4. For a complete description of other details of this switch structure reference may be had to the abovementioned patent.

Referring now to Figs. 3, 4 and 5, itwill be noted that the cards l6 and I? are secured and looked as follows to the contact springs l3 and I5, respectively. Referring specifically to one of these cards for example card it, it will be noted that this card has a series of slots 25 and 26 cut diagonally and symmetrically on opposite'sides thereof. These slots are wider than the thickness of the springs 53 and as the springs it are bifurcated from their outer tips to the place where the cord is located, these bifurcated portions, such as 21 and 28 of the first spring of the group i3, straddle the portion 30 of the card between the slots 25 and 2E. The slots 25 and 26 are therefore so cut that each spring ,will be securely held by the card. The portion 2'! will therefore engage at its inner left-hand lower edge the inner left-hand corner 3| of slot- 25. (lookin at Fig. 4) and atits upper right-hand side, the upper right-hand edge 33 of slot 25; while the portion 28 will engage atits left-hand upper edge the inner left-hand corner 3'! of slot 26 and its lower right-hand side the lower righthand edge 35 of the slot 26. The portion 30 fits therefore into the enlarged circular hole39 at the bottom of the bifurcation as shown in detail in Fig. 5. Card It may be held in, this position transversely across the springs l3 by the protrusions it and l! raised on the springs l3 against which one side of the card It may rest. The opposite side of the card may restagainst the flat surface 42 on the vertical contactstrips M. 43 on this strip M as shown in Fig. 4. It should be noted that this outer vertical contact strip is also provided between the portions 42. and 43 with the rearwardly extending portions 4-? and that the cards it and H have projections 48 and 49 that may respectively engage the portion 4'! on transversely opposing edges. This holds the springs l3 and ram proper fixed relations to the vertical contact strips Hl. at the ends opposite to the projectionsv '48. and 49 have cut-out sections 50 and 5| to permit, the contact finger E8 to be placed in these cut-out sections when the cards are to be actuatedas will'hereinafter be described. Thecards it may be inserted in the springs I3 by sliding it edgewise between the bifurcations 2i and 28 and then turning it at right angles to the springs in the hole 38 and, when assembling the parts, the outer vertical strip M is inserted so that the projection 4? will extend between the cards l6 and ,I1 and the flat surfaces 42 and lii will rest against the projections 18 and 49 of the cards l6 and I1. By properly placing the slots 25 and 26 and cutting the projections 48 and 49 in relation to these slots, the springs l3 and'lfi. may beproperly adjusted in relation to the vertical strips l4 when the parts are in normal position. i

The operation of the-switch structure to. which the applicants invention has been applied may be described in connection with the perspective The card ll rests against the flat surface The cards I6 and ll 7 mally if the finger I8 is in its central position as shown in Fig. 3, this projection 51 will merely engage the finger [8 to move it towards the springs but will havesno effect as far as establishing contacts is concerned. However, if the finger I8 is moved upward as mentioned, it will be moved in the same direction as the projection 51, 7

but as the finger now straddles the upper slot 58, the finger will engage the section 50 of the card It and thus cause the card l6 to be moved in the same direction as the projection 51. If reference is made to Fig. 4, the card. IE will be moved in the direction shown by the'arrow and thus cause the springs i3 to contact respectively with .the horizontal springs 14. The bar 5 may thenreturn to normal while finger I8 is held in engaged position by the projection 5T of bar 5 to maintain the connection established between the contact springs. On the other hand if bar 5 is moved in the opposite direction by the magnet 2! operating on armature 60, this'finger will be lowered to be placed in front of the section 5|, and when the bar 6 is then rotated, projection 5! will engage the finger and it will be moved against the section 5| and move the card ll to establish connections between the contacts l5 and M. V

What is claimed is:

1. In combination in a switch of intersecting rows of separately operable contact sets, the contact sets at each intersecting point comprising a. group of stationary contact springs and a group of movable contact springs, contact operating. cards each individual to a groupof movablecontact springs and secured thereto to move said movable contact springs to make contact individually with the corresponding associated stationary contact springs, each of said cards being. secured to a series. of said movable springs by having opposing slots in said cards and by having two prongs on each movable spring engaging opposing slots at right angles to the cards, said opposing, slots'b'eing wider than the thick ness of the. spring but cut on a bias so: that the prongswill be held securely in said slots, selecting barsv having selecting fingers thereon individual to the several contact sets and projecting into proximity with the corresponding card, means for actuating any one of said selecting bars to move the fingers thereof into operative positions with respect to. the associated cards, holding bars and means. for actuating'any' one of said holding bars to engage and move a positionedrselecting finger and the associated card to close the associated movable contact springs into engagement with the associated stationary contact springs.

2. In combination in a switch of. intersecting rows of separately operable contact sets, the contact sets at each intersecting point comprising a group of stationary'contact springs and a group of movable contact springs, contact operating cardseach individual to a group of movable contact springsand secured thereto to move said movable contact springs to make contact individually with the corresponding associated stationary contact spring, each of said cards being secured to a series of said movable springs by having two opposing slots'cut on a bias in said cards for each movable spring and wider than the thickness of the spring and having a longitudinal slot cut in each spring slightly wider than the thickness of the card and a circular opening at the bottom of the slot in each spring of a diameter approximately the same as the width of the portion of the card between two opposing slots, said card being inserted through the slot into said circular opening in the spring and turned into the opening at right-angles to the spring, projections on said springs located so as to hold the card in said right-angled position, selecting bars having selecting fingers thereon individual to the several contact sets and projecting into proximity with the corresponding card, means for actuating any one of said selecting bars to move the fingers thereof into operative positions with respect to the associated cards, holding bars and means for actuating any one of said holding bars to engage and move a positioned selecting finger and the associated card to close the associated movable contact springs into engagement with the associated stationary contact springs.

3. In combination in a switch of intersecting rows of separately operable contact sets, the contact sets at each intersecting point comprising a group of stationary contact springs and a group of movable contact springs, contact operating cards each individual to a group of movable contact springs and secured thereto to move said movable contact springs to make contact individually with the corresponding associated stationary contact springs, each of said cards being secured to individual movable springs by having two equal slots wider than the thickness of the movable springs cut in opposing edges of the card for each spring, said slots being cut at equal angles to the longitudinal direction of the card and in a downward direction and by having each movable spring bifurcated with the prongs formed thereby inserted in said slots at rightangles to the card so that each prong rests at its inner edge in the corner of a slot and so that the outer lower edge of the slot rests against the surface of the prong near the outer edge thereof, selecting bars having selecting fingers thereon individual to the several contact sets and projecting into proximity with the corresponding cards, means for actuating any one of said selecting bars to move the fingers thereof into operative positions with respect to the associated cards, holding bars and means for actuating any one of said holding bars to engage and move a positioned selecting finger and the associated card to close the associated movable contact springs into engagement with the associated stationary contact springs.

4. The combination in a. switch of intersecting rows of separately operable contact sets, the contact sets at each intersecting point comprising a group of stationary contact springs and a group of movable contact springs, each movable spring being formed with two prongs at the end thereof, contact operating cards each individual to a group of movable contact springs and secured thereto to move said movable contact springs to make contact individually with the corresponding associated stationary contact springs, each of said cards being associated with a. series of said movable springs by having two opposing slots cut in said cards for each associated spring and having the prongs of each associated spring engaging said slots at right angles to the cards, said slots and prongs being so shaped that when a card is turned to this right-angle position the springs and the card lock in fixed cooperative relation to each other, selecting bars having selecting fingers thereon individual to the several contact sets and projecting into proximity with the corresponding card, means for actuating any one of said selecting bars to move the fingers thereof into operative position with respect to the associated cards, holding bars, and means for actuating any one of said holding bars to engage and move a positioned selecting finger and the associated card to close the associated movable contact springs into engagement with the associated stationary contact springs.

5. The combination in a switch of intersecting rows of separately operable contact sets, the contact sets at each intersecting point comprising a group of stationary contact springs and a group of movable contact springs, each movable spring being formed with two prongs at the end thereof, contact operating cards each individual to a group of movable contact springs and secured thereto to move with said movable contact springs to make contact individually with the corresponding associated stationary contact springs, each of said cards being associated with a series of said movable springs to move them by having two opposing slots cut in said card for each associated spring and having the prongs in each associated spring engaging opposing slots at right angles to the cards, said slots and prongs having configura tions coacting to hold the card between the prongs in the right-angle position so that the springs and the card move together, selecting bars having selecting fingers thereon individual to the several contact sets and projecting into proximity with the corresponding card, means for actuating any one of said selecting bars to move the fingers thereof into operative position with respect to the associated cards, holding bars, and means for actuating any one of said holding bars to engage and move a positioned selecting finger and the associated card to close the associated movable contact springs into engagement with the associated stationary contact springs.

SIGURD J. STOCKFLETH. 

